Impetigo contagiosa was studied statistically in 1977-1979 with regard to the relation between ages and months of the outbreak, and weather conditions. Species and strains of bacteria isolated from the lesions and their sensitivities to antibiotics were also determined. The main affected ages were one to five, and the disease broke out most in July and August. A high temperatures with long exposure to the sun was considered to stimulate the occurrence of the disease. Staphylococcus aureus was predominantly isolated from the lesions. The order of the sensitivities of the isolated Staphylococcus aureus to antibiotics was MDIPC, CEX, GM>CP>TC>ABPC, AMPC>EM. The sensitivities to MDIPC, CEX and GM were of 100% or nearly 100%, and the sensitivity to EM was about of 50% or less.